Education Corner

What is Hepatitis B? Hepatitis B is a type of viral hepatitis that can cause acute hepatitis and may lead to chronic liver diseases like cirrhosis and liver cancer. The incubation period ranges from six weeks to six months. Approximately 5–10% of adults and 70–90% of infants infected with Hepatitis B fail to clear the virus completely and become chronic carriers, serving as sources of transmission.   Is Hepatitis B prevalent?Hepatitis B infection occurs worldwide, with over two billion people having been infected; about 350 million are chronic carriers. It is endemic in Southeast Asia, and Hong Kong has a moderate infection rate.   How is Hepatitis B transmitted?The virus is present in high amounts in the body fluids of infected persons, mainly blood, amniotic fluid, semen, and vaginal secretions. Transmission routes include: Mother-to-child contact: Around childbirth or infancy, infected mothers can transmit the virus to their babies, with a transmission rate as high as 90%. This is the primary route in highly endemic areas like Hong Kong and China. Blood contact: Through cuts, abrasions, mucous membranes contacting infected blood or secretions, sharing needles for drug use, improper sterilization of tattoo, piercing, or acupuncture instruments, and sharing personal items like razors or nail clippers that may cause skin damage. Sexual contact: Unprotected sexual activity with infected persons.   How to prevent Hepatitis B?Hepatitis B is a bloodborne disease; preventive measures align with other blood transmissible diseases: Careful wound cleaning and dressing. Wearing gloves and disinfecting contaminated objects with household bleach when handling blood or bodily fluids. For blood-contaminated surfaces or objects: Clean with absorbent disposable material, then disinfect with a 1:4 bleach-to-water solution for 10 minutes before rinsing. For blood-stained clothing: Soak in a 1:49 bleach-to-water solution for 30 minutes before washing. For bodily fluid contamination: Clean with absorbent material then disinfect with 1:49 bleach solution for 30 minutes before rinsing. Avoid sharing razors, toothbrushes, nail clippers, syringes, or needles. Avoid tattoos, acupuncture, eyebrow embroidery, mole removal unless disposable or properly sterilized equipment is used. Reduce the number of sexual partners, practice safe sex with condoms, and if a partner is infected, get vaccinated promptly. Vaccination:The most effective prevention is the Hepatitis B vaccine, requiring three doses (first and second doses one month apart, second and third doses five months apart). After full vaccination, 90–95% develop lifelong protective immunity. Blood tests before vaccination determine eligibility—only those never infected receive the vaccine.   Who should get vaccinated? Newborns Family members and sexual partners of infected individuals Injection drug users Frequent recipients of blood or blood products Patients on dialysis Healthcare workers exposed to blood or body fluids Can chronic Hepatitis B be cured ? Chronic carriers should have regular medical checkups, including liver function and related tests, and periodic liver ultrasounds. Antiviral medications like entecavir and tenofovir suppress viral replication to reduce liver damage. Immunosuppressive treatments are carefully managed by doctors.   Source: https://www.info.gov.hk/hepatitis/english/hep_b_set.htm

What is colorectal cancer?According to the 2009 statistics from the Hospital Authority’s Hong Kong Cancer Registry, colorectal cancer ranks second among all cancers in Hong Kong in terms of incidence and mortality. Colorectal cancer primarily develops from intestinal polyps through a process that can be symptomless and takes about 10 years. Early detection and removal of polyps can reduce the chance of progression to cancer. Therefore, it is recommended that people aged 50 or above undergo regular colonoscopy screenings. Those with a family history of colorectal cancer or other high-risk factors should consider earlier screening (from age 40 or 10 years before the relative’s diagnosis) and more frequent examinations for prevention. What is a colonoscopy?Colonoscopy is an endoscopic examination of the lower digestive tract using a soft tube about 1.3 cm in diameter with a camera at the tip. It examines areas including the terminal ileum, cecum, colon, rectum, and anus to detect tumors, polyps, inflammation, or bleeding. If needed, doctors may take tissue samples for biopsy or remove polyps during the procedure. Since most colorectal tumors develop from polyps, early detection and polyp removal help reduce disease incidence. As such, colonoscopy is an effective colorectal cancer prevention method. Who should get a colonoscopy? People aged 50 and older Those with a family history of colorectal cancer Individuals with a history of colorectal polyps People with chronic diarrhea Those with blood in the stool People with changes in bowel habits (such as constipation or diarrhea)   What preparation is needed before a colonoscopy? The bowel must be thoroughly cleaned for clear observation, so patients take prescribed laxatives before the procedure. Patients with diabetes, hypertension, heart disease, kidney disease, those on low-salt diets, taking medications, or pregnant or breastfeeding women should inform healthcare providers and follow guidance carefully. Details of all medications, especially those affecting blood clotting or allergies, should be provided. Avoid high-fiber foods 3 days before the exam. Only consume liquids 1 day before the exam. Drink clear, fiber-free drinks up to 4 hours before the exam. Arrive 30 minutes early. Bring a companion—do not drive yourself home. For same-day gastroscopy, fast from solid and liquid foods for 6 hours beforehand. Healthcare staff will explain the procedure and risks, and patients must sign a consent form.   What is the procedure like? Remove metal objects, jewelry, or dentures. Lie on your side with knees bent. Sedation is given through an IV; the procedure usually takes 30–60 minutes depending on complexity. Afterward, rest in the recovery room until sedation wears off. Due to sedation, it’s safest to have a companion for the trip home. Avoid eating for 1–2 hours post-procedure. Some abdominal bloating or mild discomfort may occur. If bleeding, severe pain, or other serious symptoms occur, seek emergency care immediately.   This content is for educational purposes only. Please consult your doctor for personalized medical advice.

  What is Hepatitis C virus? • Hepatitis C virus (HCV) is a small RNA virus that causes liver damage. Like hepatitis B carriers, some hepatitis C carriers develop chronic hepatitis, liver scarring or liver cancer.• The incubation period is 6-9 weeks (ranges from 2 weeks to 6 months).• A majority of people infected with HCV do not have symptoms or signs. If symptoms and signs occur, they are indistinguishable from those of hepatitis A or hepatitis B virus infections. About 80% of acute infections do not clear the virus and chronic infections ensue.• To test for hepatitis C infection, HCV Ab and HCV RNA are used.• The risk of liver failure and liver-related death from HCV increases for those who are co-infected with human immunodeficiency virus (HIV).Epidemiology• Worldwide, HCV prevalence is directly related to the prevalence of persons who routinely share injection equipment and to the prevalence of contaminated parenteral practices in health care settings.• WHO estimates that 2-3% of world population is chronically infected with HCV.• It has been estimated that less than 0.5% of the general population in Hong Kong carry hepatitis C virus, but the infection rate is higher among injecting drug users.   How is Hepatitis C transmitted?Hepatitis C is spread in a similar way as hepatitis B, mainly through blood contact by:• sharing needles or 'works' when shooting drugs,• needlesticks injuries or sharps exposures on the job,• vertical transmission from an infected mother to her baby during labour.Less commonly, a person can get Hepatitis C infection via sexual contact. The risk increases among men who have sex with men, for those who have sexually transmitted infection, engage in rough sex, or are infected with HIV.   How to prevent Hepatitis C?There is no vaccine available against hepatitis C. The following preventive measures should be taken to prevent hepatitis C:• Do not shoot drugs. If you shoot drugs, stop and get into a treatment programme. If you cannot stop, never share needles, syringes, water, or 'works'.• Do not share personal care items (e.g. razors, toothbrushes) that are potentially contaminated with blood.• HCV infected persons should not donate blood, organs, or tissue.• Health care worker should always follow routine barrier precautions and should handle needles and sharps safely.• Use latex condoms correctly and every time when you have sex.How to cure Hepatitis C:• HCV positive persons should be evaluated by their doctor for liver disease.• Drugs, such as Interferon, Pegylated Interferon and Ribavirin, can be used to treat the infection. Treatment should take into consideration of severity of disease, contraindications, and likelihood of successful response.Source: https://www.info.gov.hk/hepatitis/english/hep_c_set.htm  

What is Hepatitis A? • Hepatitis A is one type of viral hepatitis. It usually leads to acute hepatitis and jaundice.• It has an incubation period of 6 days to 6 weeks.• Most patients have a complete recovery. The liver may be severely affected in a few cases.• Persons recovered from the infection develop lifelong immunity against the infection. There is no chronic carrier state.Epidemiology in Hong Kong• Hong Kong is a region with low prevalence of hepatitis A.• The recent outbreak in 1992 resulted in more than 3000 cases and 4 deaths.• Annual reported cases of hepatitis A in Hong Kong fell from over 1000 in 1988 to only a few hundreds in recent years.• Most of the people in Hong Kong below the age of 40 have never been infected.   How is Hepatitis A transmitted?Hepatitis A is transmitted faeco-orally - the virus is transmitted from an infected person's stool to the water or food eaten by another person.The virus can survive in water for more than a year and also in food for a few days, therefore it can be transmitted by:-• eating contaminated food (especially shellfish like oysters, clams, cockles and mussels) without proper cooking;• drinking contaminated water;• close personal contact with infected person.   How to prevent Hepatitis A?To be careful with your personal, food and environmental hygiene.• Personal hygiene - wash your hands with soap before preparing or eating food and also after going to the toilet.• Food hygiene - drink only boiled water. All food, especially bivalve shellfish such as oysters, clams, mussels, and scallops, etc., should be carefully cleaned and thoroughly cooked.• Environmental hygiene - treat contaminated water and sewage properly; store drinking water properly and keep all kitchen utensils clean.   How long does it need to develop antibody after injecting Hepatitis A vaccine? Being vaccinated against hepatitis A helps to produce antibodies to the virus. A complete course of vaccination requires 2 injections, given 6 months to 12 months apart. The body takes 4 weeks to develop antibody against hepatitis A after the first vaccine injection. Hepatitis A vaccine is not licensed for children younger than one year of age.   Who is not available to inject Hepatitis A Vaccine? 1. As adults who are over 40 years old may already developed immunity against hepatitis A, hepatitis A serostatus should be checked before vaccination so as to avoid unnecessary injections.2. Anyone who has ever had a severe life-threatening allergic reaction to the previous dose of hepatitis A vaccine or allergy to any vaccine component should not get another dose.3. People who travel frequently to places with a high prevalence of hepatitis A will have a higher chance of getting infected.4. People who frequently eat uncooked shellfish also have a higher chance of being infected.5. Hepatitis A vaccine can be used to prevent infection, however, it does not substitute personal and food hygiene.6. Data from abroad show that male homosexuals and bisexuals have a higher chance of being infected.7. Infected food handlers stand the high chance of spreading the infection to others.8. The safety of hepatitis A vaccine for pregnant women has not been determined, although there is no evidence that it is harmful to either pregnant women or their unborn babies. Pregnant women should preferably consult doctor for the appropriateness of hepatitis A vaccination. Source: https://www.info.gov.hk/hepatitis/big5/hep_a_set.htm    

Why do I need to inject MMRV vaccine?  Measles, Mumps, Rubella and Varicella are common child diseases that spread by airborne transmission of droplets from the respiratory tract. Among them, Varicella is caused by contact with vesicle fluids of the skin lesions. The disease may be complicated by encephalitis, or even fatal in severe cases. Young children should receive the first dose of MMRV Priorix-Tetra Vaccine at one year of age, followed by the second dose at 15 months to 6 years. Moreover, the side effects of the vaccine are mild.

What is Varicella infection?  Varicella (also known as chickenpox) is a viral illness caused by the varicella-zoster virus. It is highly contagious and is spread by airborne transmission of droplets from the respiratory tract or from the vesicle fluid of the skin lesions of chickenpox or herpes zoster infection. Affected persons present with fever and itchy rash. The rash usually develops over 5 days with formation of vesicles and appears first on the scalp and face, moves to the trunk and then to the limbs. The rash occurs mainly over the trunk. The vesicles are itchy, and then dry up and form a scab in around 3 days. Affected persons usually recover in 2 to 4 weeks. Varicella is usually a mild disease of childhood. It is more severe in adults and in individuals of any age with impaired immunity. The disease may be complicated by skin infection, aseptic meningitis, encephalitis and pneumonia. Infection in early pregnancy may be associated with congenital malformation of the fetus. What is Varicella Vaccine?  A. Why get vaccinated? Varicella vaccine can effectively prevent chickenpox infection. In Hong Kong, Varicella vaccine is included in the Hong Kong Childhood Immunisation Programme. B. When should my child get vaccinated? Children should receive two doses of Varicella vaccine.  The first dose is given at one year of age. The second dose is given when the children reach primary one. C. The following individuals should NOT receive Varicella vaccine or should wait In the Maternal and Child Health Centres, the type of varicella-containing vaccine given to children is monovalent varicella vaccine. Persons who have the following condition should not receive the monovalent varicella vaccine or should wait: serious allergic reaction to a previous dose of Varicella vaccine known history of severe allergy to gelatin or certain antibiotics individuals with the following conditions: cancer on long term corticosteroids immunodeficiency moderate or severe acute illness received immunoglobulin or other blood products (e.g. blood transfusion) within the past 11 months received other live vaccines in the past four weeks untreated active tuberculosis family history of congenital or hereditary immunodeficiency pregnancy (women in reproductive age should avoid pregnancy for three months after vaccination) D. What are the side effects? In general, monovalent varicella vaccine is safe and well tolerated. Its adverse reactions include the following:- Local  reactions,  such  as  pain, redness and rash at the injection site. These are usually mild and self-limited. Systemic  symptoms  such  as  fever  and  generalised  skin  rash  occur  less frequently. Latent infections leading to herpes zoster have been reported but the majority of cases have been mild and have not been associated with complications. Children should avoid taking salicylates (e.g. aspirin) within 6 weeks after receiving varicella vaccine. Rarely, the varicella virus in the vaccine may transmit from vaccine recipients who develop a varicella-like rash to susceptible high-risk individuals (e.g. immunocompromised, pregnant women without immunity to chickenpox, newborn infants of mothers without immunity to chickenpox, all newborn infants born at less than 28 weeks gestation). However, it is not a contraindication for a child to receive varicella vaccine just because there is high risk individual in the same household. A pregnant mother or other household pregnant member is also not a contraindication for immunisation of a child in the household. No precautions are needed following immunisation of a child who does not develop a rash. However, if the child develops a rash post-vaccination, high risk individuals should avoid close contact with the child until the rash has resolved.